Originally Posted by
GMC-2002-Dmax
All LBZ, LMM and LML ECM's are only locked from a read if flashed with the Anti-Read Patch when flashing a EFI-Live File into any of those ecm's.
In 10+ years I have never encountered any LBZ, LMM or LML report a $0537 code on a flash.
If the ecm can be read out, it is not locked, I m not sure how a custom key gets set on a LMM, I can send you a file with a few changes to try alternate keys and assume the lock may be faulty.
PM me your email, or call my shop 854-444-2874 and Vince will help you with the issue.
An updated file has been sent to Vince for your Autocal